Pyrefly: A new type checker and IDE experience for Python

Today we are announcing an alpha version of Pyrefly, an open source Python type checker and IDE extension crafted in Rust. Pyrefly is a static type checker that analyzes Python code to ensure type consistency and help you catch errors throughout your codebase before your code runs. It also supports IDE integration and CLI usage to give you flexibility in how you incorporate it into your workflow. The open source community is the backbone of the Python language. We are eager to collaborate on Pyrefly with the community and improve Python’s type system and the many libraries that we all rely on. Get started Ready to dive in? The official Pyrefly website has all the details, but to quickly get started: Why we built Pyrefly Back in 2017, we embarked on a mission to create a type checker that could handle Instagram’s massive codebase of typed Python. This mission led to the birth of the Pyre type checker, inspired by the robust designs of Hack and Flow, and written in OCaml to deliver ... Read full article.